Some people have real life stuff to take care of, so chances are they're unable to get on when the patch drops. If anything, you should be happy for new people. Explain the fight to them and just be patient. It's not like everyone else was any better when all of that first dropped. Sure, they had to learn the hard way, and there were no videos to watch. But, isn't our job to help teach other players how things go? As a mentor, I take great pride in helping other players, whether they be new adventurers, returners, or even other mentors themselves. While I'm not much of an Extreme runner or raider myself, I still will teach new people in the duty how to do mechanics.